“The air,” Gerald Whitmore gasped, his fingers clawing weakly at his collar.

His face was turning a dark, mottled purple, and his breathing was loud and wet.

“Mr. Whitmore, lean forward,” I said, reaching down to grab his shoulder.

His silk tie was soaked with sweat, and his body felt completely limp as he slumped sideways.

Across the aisle, the elderly woman’s eyes rolled back, her chin dropping heavily against her collarbone.

A collective groan rippled through the first-class cabin as more passengers began to sway in their seats.

Some were coughing violently, while others simply drifted off, their hands dropping to their laps like lead weights.

The sweet, chemical odor grew thick, coating my tongue with a taste like burnt copper.

My head throbbed instantly, a sharp needle of pain driving straight between my eyes.

“Sarah!” I called out, turning toward the forward galley.

My voice sounded distant and muffled to my own ears.

Sarah was clinging to the edge of the galley counter, her knees buckling as she tried to stand.

“Grace, I can’t… I can’t breathe,” she whispered, her eyes wide with fear.